Provided herein are methods for preparing a sequencing library that includes nucleic acids from a plurality of single cells. In one embodiment, the sequencing library includes whole genome nucleic acids from the plurality of single cells. In one embodiment, the method includes generating nucleosome-depleted nuclei by chemical treatment while maintaining integrity of the nuclei. Also provided herein are compositions, such as compositions that include chemically treated nucleosome-depleted isolated nuclei.